Abstract

As heating loads decrease due to improved energy performance, conventional boiler control methods are increasingly prone to overshooting. This study compares the performance of three control strategies BB (Bang Bang control), RC+BB (Return Control+BB), and OR+BB (Outdoor Reset control+BB) in an 84-type apartment. OR+BB reduced overshooting duration by 42.8% and peak temperature by 0.61°C, RC+BB shortened the duration by 46.1% and reduced peak temperature by 0.59°C. However, both OR+BB and RC+BB caused short cycling under low-temperature conditions, indicating potential reductions in boiler and system efficiency. Further investigation is required to optimize control under reduced load scenario.